Giant Cell Arteritis (GCA) Clinical Trials and Treatments

Giant Cell Arteritis is a systemic vasculitis affecting large and medium-sized arteries, with primary involvement of the external carotid artery system and its branches, particularly the temporal artery. The disease results from T cell-mediated granulomatous inflammation with characteristic giant cells and macrophage infiltration of the vessel wall. Pathologic findings typically show granulomatous inflammation with giant cells centered at the internal elastic lamina.

The most common symptoms of Giant Cell Arteritis include New-onset headaches in scalp, forehead, or temples, Jaw claudication (pain while chewing), Vision loss or blindness from arteritic anterior ischemic optic neuropathy, Shoulder and hip pain from associated polymyalgia rheumatica, Fever and constitutional symptoms, among others. Approximately 10-20 cases per 100,000 people over age 50; incidence increasing with age, peak in 8th decade. Symptoms can range from mild to severe and may vary between individuals.

Trial Friend lists all active clinical trials for Giant Cell Arteritis from ClinicalTrials.gov, with eligibility criteria translated into plain English. Patients can filter by trial phase and recruitment status, search by location, and use the Match Me tool to score trials against their profile. Treatment for Giant Cell Arteritis is rapidly evolving, with newer biologic therapies offering the promise of reducing dependence on corticosteroids while maintaining disease control. Two steroid-sparing medicines are FDA approved for adults with GCA, each used alongside a steroid taper: tocilizumab (Actemra), an IL-6 receptor blocker given by injection under the skin or by IV infusion, approved in May 2017, and upadacitinib (Rinvoq), a once-daily JAK inhibitor pill, approved in April 2025.

Yes. As of October 21, 2026, 3 FDA-approved medicines have a current label that names Giant Cell Arteritis: Actemra (tocilizumab), first approved in 2010; Rinvoq (upadacitinib), first approved in 2019; and Corticosteroids (dexamethasone, methylprednisolone, prednisolone, triamcinolone, betamethasone, hydrocortisone). Corticosteroids and immune globulins count once each.

The exact cause of Giant Cell Arteritis is not fully understood. It is not caused by a single gene; inherited variants raise risk, and immune, environmental or other triggers are thought to set it off. HLA-DRB1*04 and other immune-gene variants raise risk, but the trigger is unknown and no genetic test has a diagnostic role. Approximately 10-20 cases per 100,000 people over age 50; incidence increasing with age, peak in 8th decade. Research is ongoing to better understand the disease mechanism.

No single gene test diagnoses Giant Cell Arteritis. The diagnosis rests on clinical findings and laboratory or imaging results; genetic variants shift risk rather than cause the disease. HLA-DRB1*04 and other immune-gene variants raise risk, but the trigger is unknown and no genetic test has a diagnostic role.

Some trials collect genetic samples for research or check specific risk markers. The Genetic Testing section of this page shows any tests listed in the NIH Genetic Testing Registry, which for this condition are usually research or risk-marker tests rather than diagnostic ones.

Eligibility for Giant Cell Arteritis clinical trials depends on factors like age, diagnosis, treatment history, and overall health. Each trial sets its own inclusion and exclusion criteria. Trial Friend translates these requirements from medical language into plain English so patients can review them more easily. The Match Me tool can score your profile against active trials to help identify studies that may be a fit.

Participating in a Giant Cell Arteritis clinical trial typically involves scheduled visits, medical tests, and close monitoring by a research team. Depending on the study phase, you may receive an investigational treatment, a placebo, or the current standard of care. Trials may last from a few weeks to several years. Study participation is voluntary, and you can withdraw at any time.